Author Topic: New Flights of Fancy -- Beyond Butterflies!  (Read 8604 times)

Dan_Lehman

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New Flights of Fancy -- Beyond Butterflies!
« on: August 30, 2009, 07:01:56 AM »
The Butterfly knot or Lineman's Loop/Rider aka "Alpine Butterfly" is fairly commonly
known among users of kernmantle ropes (rockclimbers, cavers, SARescue) and in
knotting circles.  That is, the knot name is known, and some method of forming
some version of it is known.  It is useful as a mid-line eye knot because it performs
well when loaded by either end and by the ends alone, being generally reportedly
strong and fairly easy to untie.  We should remember that Paul Kruze (? IIRC) however
reported testing it in (again, IIRC) thick, flexible, soft-laid nylon rope and finding it
to be weaker than the bowline (and rather weak, absolutely).  We should also note
that the knot can be oriented in various ways, and that being asymmetric it is of
a different geometry per end.

Some people (in the caving world, and UK caving world i.p., I think, so far)
have taken to regarding a like knot --viz., Ashley's #501 (fuse arrowed ends
together (I don't readily find the exact eyeknot))-- as "Butterfly" and made
the Lineman's Loop "Alpine" (which fits with one publication source, anyway).

One concern about the Butterfly is that it can jam on certain loadings and
orientations -- the eye leg that feeds into the collar around the unloaded
end can be drawn snug around it, very tightly.

So, here are some *new* knots of the same sort, and ones that can be
oriented in anticipation of a "directional" loading such that they don't jam.

The first knot shown is a simple variation on the Butterfly which I verbally
presented in the "Knot testing - Life support knots - procedures and results"
thread --> http://igkt.net/sm/index.php?topic=1239.45#msg10158
By putting an extra half turn/twist into one half of the knot during tying,
that half will form a Fig.8 and be resistant to jamming.  (The red PMI knot
is a bottom view of the knot below.)

The second knot shown is a mid-line eye knot corresponding to Ashley's
bend #1408.  The photo shows (crudely, but hey ... !) the knot being
formed, from left rope to right; the thick yellow PP rope serves as a
kind of physical arrow in seizing the inchoate eye and pointing to the
path to tuck it out; the central blue CoExOlefin shows the knot loosely
tied, and then the red PMI E-Z Flex holds a lightly tensioned knot.

Beyond this is a variation of the Butterfly itself with the sort of extra
eye-leg wrap seen for the #1408 variation -- which surprised me, as
I thought that structure was only a penalty to getting the otherwise
symmetric #1408 into mid-line state, and that the Buttefly's asymmetry
was its price; but, in fact there is this other variation.  (later)

--dl*
====


« Last Edit: August 30, 2009, 07:25:04 AM by Dan_Lehman »

Mike

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #1 on: August 30, 2009, 05:00:39 PM »
Dan, I tried your instructions on the extra half twist, except I put an extra half twist in both sides.  One in one direction and one in the other direction.  This does make a nice symmetrical alternative that seems to be "Jam Proof"

Dan_Lehman

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #2 on: August 30, 2009, 05:53:33 PM »
This does make a nice symmetrical alternative that seems to be "Jam Proof"

But you've gone one extension beyond what's needed -- I don't find any
jamming in the 1st (Fig.8 & Overhand) structure.  Moreover, you've lost the
nice benefit of having the two ends load the the knot in the same rotation
vs. pulling in opposite ones.  Going the same way means that the eye legs are
twisted ever tighter together.

Here I should remark that it seems that the torsion imparted into the eye
by the "twirly flop" tying method runs against the desired orientation of
the eye legs so that they indeed are drawn ever tighter in twist.  (Looks
like a job for Alpineer! )

None of these knots (original & two revisions) is symmetric.

--dl*
====


Mike

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #3 on: August 30, 2009, 06:10:12 PM »
I'm not sure why the rotation you are talking about makes any difference?

When I said Symmetrical, I was refering to being the same on either side (left/right) as pictured.  

In the version I posted with the extra half twist on bothe sides, I really like how the knot does not cinch down on itself. .  I was able to pull as hard as i could and it still kept the shape as seen in the picture. Of course, this may not hold true for other types and sizes of rope.
« Last Edit: August 30, 2009, 06:18:15 PM by Mike »

Dan_Lehman

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #4 on: August 30, 2009, 07:54:34 PM »
I'm not sure why the rotation you are talking about makes any difference?

Because it enables certain positioning of the eye legs to be held constant.
Whereas in the case of opposing rotational draws by the ends, one cannot
be so assured of positioning -- YMMV re particular dressing and such.
(FYI, I loaded my Buttefly8 and got a very nice-looking bend in the
S.Part, which to me implies strength, kindness to the rope (no hard
pressure at one point) -- untested, mind.)
Ashley remarks re his bend #1408 about the differences in how its
ends can be positioned, with one way leading to ever tighter binding,
and the other to a chance of the ends being walked out of the knot.

Quote
In the version I posted with the extra half twist on bothe sides, I really like how the knot does not cinch down
on itself. .  I was able to pull as hard as i could and it still kept the shape as seen in the picture.
Of course, this may not hold true for other types and sizes of rope.

How hard was "as hard as I could"?  You picture 11?mm (9?) Bluewater II
low-elongation kernmantle rope with a strength around 6_000#; a "hard"
loading of that would be half a ton (or tonne!); I'll guess that your pull
wasn't in that neighborhood.  I use a 5:1 pulley (crummy, though), and
thus can get several hundred pounds force on knots; believe me, some
things can happen that you might not expect from manual (even w/leg)
loading!  -- better have a good idea about untying the knot beforehand,
or you might make it a permanent souvenir (or face some serious effort
with a marlinespike/screwdriver/etc.) !

What I look for, as suggested above, is the absence of an (early) hard
turn in the S.Part.  Often, the way the Butterfly is tied (also Rosendahl's
Zeppelin and SmitHunter's Bends), there is a pretty hard turn around
a single diameter of rope (here, the nipped ends).  I think that this isn't
good (again, don't have solid, certain tested data on this), and that by
some careful dressing one can do much better.  Untying knots that have
held that pulley-inflicted several-hundred-pounds load can show what
the high-pressure areas look like -- concentrated, or distributed.

--dl*
====

alpineer

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #5 on: December 01, 2009, 09:08:51 AM »
[quote   (Looks like a job for Alpineer! )

--dl*
====


Okay! Here's one good way to build the B8 while managing eye torsion. Start with an oversize 'Larksfoot on the Left  thumb'. Orient the Larksfoot so the END of the bight crosses above the two parallel Standing lines. Then BACKTWIST the Standing lines as in the Hybrid Method of tying the Alpine Butterfly. Slip your R. hand between the STANDING lines and hook the OUTSIDE of the Loop on the FAR side of the Larksfoot with your R. thumb. DO NOT pull the Loop off the end of  your L. thumb. Continue from here as you would for the 'Hybrid Method'. The Eye Legs will be rendered with twist in the desired direction :)


A host of knots (some new?) can be tied which utilize the 'Hybrid' concept. Some may be of interest.

alpineer  
« Last Edit: December 01, 2009, 04:37:28 PM by alpineer »

Dan_Lehman

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #6 on: December 03, 2009, 06:28:12 AM »
Unknotted:  when I Search'd for 'hybrid', I found just this msg.,
which was what for me (and I imagine others) needed the search
and explanation.  I got as far as Cow-hitching my left thumb with
the orientation of having the bight over (not "above"),
and there I was left, purely unhybridized.

 :-[

alpineer

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #7 on: December 03, 2009, 09:13:50 AM »
Unknotted:  when I Search'd for 'hybrid', I found just this msg.,
which was what for me (and I imagine others) needed the search
and explanation.  I got as far as Cow-hitching my left thumb with
the orientation of having the bight over (not "above"),
and there I was left, purely unhybridized.

 :-[

 Hey Dan,

I've been fiddling knots for about decade in a vacuum, and I'm new to this forum stuff, but please continue to hang in there with me and I'm sure my communication skills will improve. I'm committed to this.

I will attempt to elaborate on my shortish description, then later I will describe another(and I think better) method for the tying of...

Continuing from Cow Hitch on the left thumb, you need to pass your right hand THROUGH/IN BETWEEN  the two hanging lines after you put a 180 deg. counterclockwise (from R. hand perspective) twist in them. Then you can reach up and GRAB/HOOK the RIGHT Half of the Cow Hitch with your Right thumb. Then pull this LOOP back through the hanging lines. Give the BIGHT that's being formed by pulling the Loop a quarter turn counter-clockwise. Now all you have to do is pass the Bight through the opening where your Left thumb is in the direction your left thumb is pointing. That's it, except for dressing and setting the knot.

alpineer

P.S.  Use a long enough cord or a climbing rope (to keep the ends away from the tying) :)
« Last Edit: December 03, 2009, 04:32:55 PM by alpineer »

Dan_Lehman

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #8 on: December 03, 2009, 06:45:35 PM »
2nd verse is worse.

Look, think of presenting mental images in a plane,
from which left/right/up/down are pretty obvious
--one could invoke N/S/E/W compass directions, also--,
and then "around behind" & "left over" make obvious
sense.

"Clockwise" needs a definite perspective; but "from R. hand
perspective" doesn't do it for me -- R-hand is in my mind on
the right, and facing two vertical strands, one behind the other.

Now, I get a Cow on my left thumb which thumb is before
me pointing rightwards, naturally; ends hang.
To twist ends counterclockwise makes no sense; if I were to
view the hanging ends from beneath the thumb, looking upwards,
then I can make such a twist -- although with the next instruction,
to pass one's right hand between the legs, that really wants about
a 270deg twist (for 180 merely puts L on R & vice versa, with
then the "between" being from the viewer's PoV and not from
the right hand's needed penetration).
One could specify the between by "behind R leg, before L", say,
with the twist part similarly specified ("move R leg leftwards OVER
the L leg; bring R hand behind the new R leg and across in front
of the new L leg, and reach up ...").

When I pull down the loop which somehow forms a bight, I end
up pulling with R hand R-wards and so it makes no sense to try
to trace my L thumb "in the direction it's pointing" -- rather, in
the reverse!?  And how does a quarter turn matter, as when just
going through the other loop isn't going to preserve that very well?!

 ???

alpineer

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #9 on: December 04, 2009, 06:43:15 AM »
2nd verse is worse.

Oooh, this is so much fun LOL. Remember that Herman's Hermits tune from waaay back in "64? "Second verse, worse than the first" woulda sent it with a bullet ;D
You are going to have to think "outside the plane" on this one Dan (inside the box will do) because plane movements don't cut it for what I'm trying to convey. My method requires some subtle hand movement, which can be difficult to suggest by words, but comes with a high degree of ergonomics (i.e. "hand friendliness"). The product is a smooth and efficient flow to the tying process. Most of the discreet steps aren't really all that dicreet. They overlap one another. And the more they overlap, the more smooth and efficient the whole tying process becomes.

Dan, from verse1 and verse 2 there are only a few permutations you can try, so just try them. Think efficiency of hand movement and you will get it. I know you didn't gain that vast and intimate knowledge of knots without having a dogged and determined spirit. And when you do get it you will understand more fully that which I've been trying to communicate.  Now I know that is "cart before the horse" logic, so please, if you could offer up a finer verbal description, and put that horse back in it's rightful place, a good thing it would be.

Next post, I will attempt to screw up verse 3 :D Then on from there to video.      
« Last Edit: December 04, 2009, 06:46:51 AM by alpineer »

alpineer

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #10 on: December 04, 2009, 07:08:19 AM »
Hmm, after some more fiddling I see the quarter turn counter-clockwise is SUPERFLUOUS. All the better.

Dan_Lehman

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #11 on: December 04, 2009, 06:01:31 PM »
2nd verse is worse.

Oooh, this is so much fun LOL. Remember that Herman's Hermits tune from waaay back in 1964?

Eh, the Hermits don't enhance the situation, for me.  (I remember.  Later, the Monkeys.)
And I don't want to be continuing to "the Eighth" on trying to figure this knot out.

Quote
You are going to have to think "outside the plane" on this one Dan (inside the box will do) ...

While the structure lies in 3D, in order to get some orientations, as I indicated,
planar guidance is helpful.  In any case, a clock face is 2D, nevermind what value
it's connoting beyond that (a 4th dimension).

Quote
... if you could offer up a finer verbal description, ...

As said above, I made a start and ran into problems, and explained why.
The next verbal step is for you to go from there and refine the words to
get past the problems.  I.e., to follow MY thinking and results and see
where it's gone astray, and then clarify what should be done -- to reply
directly to my effort.  And this might require making some rather
unsmooth, planar snapshot(s) for clarity at the point -- how things should
be oriented, and what move follows.

A final point:  doing whatever, by the limited instructions so far given,
I come up with a slip-knot/noose -- the right end feeds into the tucked
right side loop of the Cow, and just pulls it back out on loading.

On the "180deg counterclockwise turn", I can see that if with my right hand
I grasp the hanging ends and pull them a little towards me as I look at the
hitch on my thumb, I then have those legs in a position where counterclockwise
turning makes sense.  (But that doesn't help me beyond that, so far.)

--dl*
====

alpineer

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #12 on: December 05, 2009, 11:41:04 AM »
Quote
On the "180deg counterclockwise turn", I can see that if with my right hand
I grasp the hanging ends and pull them a little towards me as I look at the
hitch on my thumb, I then have those legs in a position where counterclockwise
turning makes sense.  (But that doesn't help me beyond that, so far.)



That's good. We are getting somwhere here.
Let's continue from "Cow on left thumb, thumb before me pointing rightwards, ends hanging."
Take "R. hanging line" in R. hand and bring "R hanging line" 180 deg. around to the L. side of the L. hanging line. You must perform this action on the YOU side of the L. hanging line.
From here, you can slip the R. Hand directly through the space between the NOW REVERSE ORIENTED hanging lines and reach up with the R. thumb and hook the R. side of the Cow from the outside of the hitch.
Pull that R. side of the Cow back through space between the hanging lines toward you to form a Bight (Let the two lines which are on the L. thumb run over the that thumb in order to do this).
What you should be looking at now are two lines over both sides of your L. thumb and one line over both sides of your R. thumb (thumbs pointing away from you), and the whole affair arranged vertically.
Next step is to re-orient this whole affair horizontally.
Now, take both thumbs out of their respective holes that have been created by all of the twistings and turnings and replace them with the fingers of the same hand. Turn the palms up as you do this, keeping elbows at your side.
Take the single loop on your R. hand side and lay it over the L. hand fingers alongside and to the right of the other two loops. Then leap frog those other two loops together over that single loop and let them drop.
Take hold of the two lines that hang below all of this knotty stuff and pull on the single loop in your L. hand. Let go of the single loop and pull the two hanging lines away from each other. Are you seeing the Butterfly 8 now with that desired eye leg twist and collar orientation?


alpineer

 
  
« Last Edit: December 05, 2009, 04:27:50 PM by alpineer »

Dan_Lehman

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #13 on: December 05, 2009, 08:14:45 PM »
I will not pursue this further -- the 3rd instructions are beyond comprehension.

 :(


alpineer

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Re: New Flights of Fancy -- Beyond Butterflies!
« Reply #14 on: December 06, 2009, 02:45:37 AM »
I will not pursue this further -- the 3rd instructions are beyond comprehension.

 :(



Well, beyond your comprehension, yes! I've offered you 3 versions and still you cannot get past the first 2 steps! THAT is beyond my comprehension. I've given you enough beta to get you there (i.e. correct twist in eye legs and properly oriented collars).
 
Anyhow, the Butterfly 8 falls short of getting full marks because it is not jam resistant in all loading scenarios, and so one has to know where the load will come from to benefit. This may or may not be an issue, but better if it's taken out of the equation altogether. In the case of a third man on the middle of a rope, as when travelling across glacier,  the preferred knot would be jam resistant regardless of loading scenario.

alpineer